In conventional practice, there have been used air-conditioning systems that use timer settings and other techniques so as to provide a specific comfortable air-conditioned environment for users returning after being outdoors. For example, a user return time is set in advance, a pre-cooling operation is performed in which the temperature is set from a predetermined time before the user return time to a temperature between the target setting temperature and the outdoor temperature, and an operation is performed for setting the temperature to the target setting temperature at the time the user returns. It is thereby possible to provide a specific comfortable atmosphere for the returning user, and to prevent the user from being discomforted when exposed to the temperature difference and allow the user to become gradually accustomed to the indoor environment.
With the air-conditioning system described in Japanese Patent Application Laid-open Publication No. 4-116328, for example, the amount of clothing worn by the user or the activity amount of the user before returning is inputted as data for air-conditioning control, and a comfortable space for the user can be quickly provided with this data taken into account.